How much concrete does it take to pour the mat foundation for a 48-story office building?

180 concrete trucks full making nine or so trips each. That’s 14,000 cubic yards, according to Hines, the Houston-based developer of the 1.05 million-square-foot building at 609 Main at Texas.

The trucks will line up in downtown Houston to start pouring the foundation at 7 p.m. Saturday, and the work will continue until the job is done. The pour is expected to take more than 17 hours.

Here’s the “before” picture of 609 Main, which is scheduled for completion in 2017. The shiny glass building in the background is BG Group Place, a 46-story building also developed by Hines and designed by Pickard Chilton. It was completed in 2011.